Description
The fix for CVE-2026-0716 (commit 6ff7ef0, libsoup 3.6.6) placed the integer overflow guard inside the if (masked) block, leaving unmasked server-to-client frames unprotected. A malicious WebSocket server can send a crafted unmasked frame with a payload length near UINT64_MAX to trigger an OOB read in a libsoup-based client when max_incoming_payload_size is set to 0.
Affected products
| Vendor | Product | Affected | Fixed |
|---|---|---|---|
| Red Hat | Red Hat Enterprise Linux 10 | — | — |
| Red Hat | Red Hat Enterprise Linux 6 | — | — |
| Red Hat | Red Hat Enterprise Linux 7 | — | — |
| Red Hat | Red Hat Enterprise Linux 8 | — | — |
| Red Hat | Red Hat Enterprise Linux 9 | — | — |
Fixed in Linux distributions
Distributions backport fixes, so the version that fixes this vulnerability differs per release — upgrade to at least the version shown. From the distributions' security trackers and advisories.
Debian
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Debian 14 | libsoup3 | 3.8.0-1 | — |
Ubuntu
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Ubuntu 26.10 | libsoup3 | 3.6.6-1ubuntu3.1 | USN-8975-1 |
| Ubuntu 26.04 LTS | libsoup3 | 3.6.6-1ubuntu0.2 | USN-8975-1 |
| Ubuntu 24.04 LTS | libsoup2.4 | 2.74.3-6ubuntu1.10 | USN-8975-1 |
| Ubuntu 24.04 LTS | libsoup3 | 3.4.4-5ubuntu0.10 | USN-8975-1 |
| Ubuntu 22.04 LTS | libsoup2.4 | 2.74.2-3ubuntu0.10 | USN-8975-1 |
Show 5 more (older releases, extended support, other products)Fewer releases
| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Ubuntu Pro 26.04 LTS | libsoup2.4 | 2.74.3-10.1ubuntu5+esm4 | USN-8975-1 |
| Ubuntu Pro 22.04 LTS | libsoup3 | 3.0.7-0ubuntu1+esm10 | USN-8975-1 |
| Ubuntu Pro 20.04 LTS | libsoup2.4 | 2.70.0-1ubuntu0.5+esm5 | USN-8975-1 |
| Ubuntu Pro 18.04 LTS | libsoup2.4 | 2.62.1-1ubuntu0.4+esm10 | USN-8975-1 |
| Ubuntu Pro 16.04 LTS | libsoup2.4 | 2.52.2-1ubuntu0.3+esm9 | USN-8975-1 |
SUSE
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| SLES 15 SP7 | libsoup | 3.4.4-150600.3.56.1 | SUSE-SU-2026:4558-1 |
| SLES 15 SP6 | libsoup | 3.4.4-150600.3.56.1 | SUSE-SU-2026:4558-1 |
| SLES 15 SP5 | libsoup | 3.0.4-150400.3.52.1 | SUSE-SU-2026:4557-1 |
| SLES 15 SP4 | libsoup | 3.0.4-150400.3.52.1 | SUSE-SU-2026:4557-1 |
| SLES 12 SP5 | libsoup | 2.62.2-5.49.1 | SUSE-SU-2026:4690-1 |
Show 7 more (older releases, extended support, other products)Fewer releases
| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| SLES for SAP 15 SP6 | libsoup | 3.4.4-150600.3.56.1 | SUSE-SU-2026:4558-1 |
| SLES for SAP 15 SP5 | libsoup | 3.0.4-150400.3.52.1 | SUSE-SU-2026:4557-1 |
| SLES for SAP 15 SP4 | libsoup | 3.0.4-150400.3.52.1 | SUSE-SU-2026:4557-1 |
| SLE Micro 6.2 | libsoup | 3.6.6-160000.3.1 | SUSE-SU-2026:23800-1 |
| SLE Micro 6.0 | libsoup | 3.4.2-17.1 | SUSE-SU-2026:22920-1 |
| SLE HPC 15 SP5 | libsoup | 3.0.4-150400.3.52.1 | SUSE-SU-2026:4557-1 |
| SLE HPC 15 SP4 | libsoup | 3.0.4-150400.3.52.1 | SUSE-SU-2026:4557-1 |
openSUSE
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| openSUSE Tumbleweed | libsoup | 3.6.6-7.1 | openSUSE-SU-2026:11316-1 |
| openSUSE Tumbleweed | libsoup2 | 2.74.3-24.1 | openSUSE-SU-2026:12084-1 |
| openSUSE Leap 16.0 | libsoup | 3.6.6-160000.3.1 | openSUSE-SU-2026:21871-1 |
Amazon Linux
| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Amazon Linux 2023 | libsoup +2 | 2.72.0-6.amzn2023.0.15 | ALAS2023-2026-3154 |
| Amazon Linux 2023 | libsoup3 +2 | 3.7.2-1.amzn2023 | ALAS2023-2026-3144 |
| Amazon Linux 2 | libsoup +1 | 2.56.0-6.amzn2.0.9 | ALAS2-2026-3970 |
Public exploits
Exploit or proof-of-concept code for this vulnerability is publicly available, which lowers the bar for attackers. Treat it as a reason to patch sooner.
Third-party code, not reviewed by us. Public PoCs are sometimes fake or contain malware. Read the code first and run it only in an isolated lab, against systems you are authorised to test.
GitHub 1 repository
-
Popy21/security-research ★ 0 · Aug 1, 2026
Vulnerability research write-ups — CVE-2026-12478 (libsoup), Apple WebKit, Google VRP
Sources: PoC-in-GitHub, Metasploit Framework, Exploit-DB — updated daily. Only links are listed; no exploit code is hosted here.
Advisories 12
- USN-8975-1 libsoup2.4, libsoup3 vulnerabilities Ubuntu Security Notices (USN) · Nov 4, 2026
- SUSE-SU-2026:4690-1 Security update for libsoup SUSE / openSUSE Security Updates · Oct 17, 2026
- ALAS2-2026-3970 Moderate: libsoup security update (Amazon Linux 2) Amazon Linux Security Center (ALAS) · Oct 12, 2026
- ALAS2023-2026-3154 Moderate: libsoup security update (Amazon Linux 2023) Amazon Linux Security Center (ALAS) · Oct 12, 2026
- openSUSE-SU-2026:12084-1 libsoup-2_4-1-2.74.3-24.1 on GA media SUSE / openSUSE Security Updates · Oct 9, 2026
- SUSE-SU-2026:4557-1 Security update for libsoup SUSE / openSUSE Security Updates · Oct 8, 2026
- SUSE-SU-2026:4558-1 Security update for libsoup SUSE / openSUSE Security Updates · Oct 8, 2026
- ALAS2023-2026-3144 Important: libsoup3 security update (Amazon Linux 2023) Amazon Linux Security Center (ALAS) · Sep 28, 2026
- SUSE-SU-2026:23800-1 Security update for libsoup SUSE / openSUSE Security Updates · Sep 27, 2026
- openSUSE-SU-2026:21871-1 Security update for libsoup SUSE / openSUSE Security Updates · Sep 25, 2026
- SUSE-SU-2026:22920-1 Security update for libsoup SUSE / openSUSE Security Updates · Jul 28, 2026
- openSUSE-SU-2026:11316-1 libsoup-3_0-0-3.6.6-7.1 on GA media SUSE / openSUSE Security Updates · Jul 21, 2026